1. Field
Subject matter disclosed herein relates to a semiconductor device and methods of fabricating same.
2. Information
Fabrication of semiconductor devices generally involves deposition of various materials, masking, etching, planarization, and/or polishing, just to name a few processes. In particular, a chemical-mechanical polish (CMP) process may be applied to a semiconductor structure to remove excess material. For example, an insulation material may be used to fill trenches to electrically isolate adjacent memory cell structures. In performing such trench filling, insulation material may overfill trenches and subsequently cover the immediate and surrounding structure. A CMP process may be used to remove such excess insulation material and to expose various layers of an underlying semiconductor structure. Particular attention, however, may be directed to applying a CMP process so that desired material layers, or portions thereof, are removed without inadvertently removing other material. For example, a CMP process may be manually terminated by an operator that observes that an intended amount of material is removed. In another example, particular material layers may be placed above layers to be retained in a semiconductor structure to act as stop layers by providing a physical buffer that slows a CMP process so that an operator may have some time to manually terminate the CMP process before an undesirable amount of material is removed. Such techniques for terminating a CMP process, however, may result in relatively large variability in structural dimensions of fabricated semiconductor devices, which may lead to variability in semiconductor device behavior, and, in some cases, device failure.